My mother's rights

We r 3 siblings n i m younger n unmarried daughter of my parents amng them.my parents,me n my brother n his family staying in 3bhk flat in chd which is in d name of my father only.For last 6 years due to my bro wife ,we hav faced so much so my muma had insisted my bro to take separate accomodation with her but he dint get agree n his wife had created a big drama in society allegating my parents falsly.but after that evn my bro dint leave the house but yes he was continue to pay the emi s of home loan which my father took a long back n failed to pay after paying for sum years due to his retirement.n thats y my father has no power n guts bfor my bro to say him anythng but he with my bro gives my mother a physical n mental torture under his influence if she ask for selling this flat or warning my son to leave this house due to which my mother faced a challenging deppression for long period but evn now their behavior is same n now as alternate my bro is offering my mother a 2bhk flat in kharar punjab n get shifted but me n my muma r asking for a plot with the construction of ground floor so that we can shift asap but my bro is making excuses of nt getting that mch loan though his own earning is mor thn 30000 n his wife is also govt teacher so taking a loan of atlist 50lakh evn is nt issue.but my father as usual is fully supporting him n nt taking responsibility of mine n my muma.but warning us for nt giving anythng frm his property if we dnt agree whatevr my bro wants.n al this is vry much spoiling to me also coz nw my age is 30 n i cant evn get married leaving my muma al alone in these torturing circumstances n i knw being unmarried i can interfere in my family matters otherwise i wil kick out so sir plz guide us what steps we can take for justice for my muma acc to our rights.Can my mother get 50% share in this flat which can be made with a lot f my mothers saccrifices though she is a housewife n if so how much time it will be taken to get it.